Obesity Falling in Some Kids, but Not All

Aug. 16, 2010 -- Obesity rates among children appear to be dropping for some groups, but not for all, new research suggests.

An analysis including more than 8 million California children and teens showed encouraging declines in obesity following a peak in 2005 among Asian and white boys and girls and among Hispanic boys.

But obesity continued to climb among African-American and American Indian girls and remained stable for Hispanic girls.

And public health efforts aimed at addressing the obesity epidemic do not appear to have had much impact for the heaviest children -- those with body mass indexes (BMIs) in the 99th percentile.

The findings can be viewed as both an encouraging and troubling report card on these efforts, researcher Kristine Madsen, MD, MPH, of the University of California, San Francisco, tells WebMD.

Published online today, the study appears in the September issue of the journal Pediatrics.

“On the one hand it is really heartening to see the declines in white and Asian children and the plateau in Latino youth,” she says. “But this is tempered by concerns about increasing racial disparities in childhood obesity. The fact that the gap appears to be widening is very troubling.”

School Soda Ban Preceded BMI Declines

The study examined body fat levels as measured by BMI among California public school children between 2001 and 2008.

California is one of the few states that require school-based BMI assessment, which is conducted in the fifth, seventh, and ninth grades.

For most groups, obesity rates peaked around 2005 -- the same year that California lawmakers banned the sale of sugary soft drinks and snacks in schools and took other actions to address childhood obesity.

Madsen says it is probably no coincidence that obesity rates began to plateau around this time and have since declined for some.

In 2008, about 20% of 8- to 17-year-old public school children in California were obese and 3.6% were severely obese, meaning they had BMIs in the 99th percentile.

American Indian children and teens had later peaks and larger increases in obesity prevalence after 2001 than any other group.

Racial disparities were greatest for the heaviest children and teens. In 2008, close to 5% of American Indian girls and 4.6% of black girls were severely obese, compared to just over 1% of white girls.